America's Test Kitchen host Chris Kimball "whisks away" some cooking myths as he talks with Morning Edition host Renee Montagne about the book he wrote, The Science of Good Cooking, with fellow Cook's Illustrated magazine editors. Being the science and cooking geeks that we are, we tuned in.

If you've ever looked up a meat recipe online, chances are it calls for a marinade. But marinating doesn't really tenderize meat. "This is your awakening," Kimball tells Montagne.

"The problem is, marinades contain acids, usually vinegar, and those break down meat but only to about a quarter of an inch of thickness. And when they break it down, they turn it to mush. They don't really tenderize it," he says.

"What does work is salting," Kimball says. "Salt gets in, it allows the protein molecules to absorb water, it loosens up the protein fibers so it retains that water and it's easier to chew." So brining meats in a mixture of salt and water and sometimes sugar is what produces a juicier meat. (Remember that, as you get ready for Turkey Day next month.)

Another myth Kimball busts is about seeding tomatoes. A lot of soup recipes call for the tedious process of ripping the seeds out of tomatoes for a smooth soup or gazpacho.

While you may get a smoother soup, you won't get one that's as tasty as it could be. "It turns out the seed in [the tomato] jelly ... has three times more flavor compounds called glutamates than the flesh, so when you seed the tomato... you're actually throwing out most of the flavor," Kimball explains.

Glutamates are what give tomatoes that meaty, umami mouthfeel. They also give MSG its flavor, but that's for another day.

Kimball tells Montagne it's totally fine to bake with cold eggs straight from the fridge most of the time, despite the fact that many baking recipes call for room-temperature ingredients.

"For years I've made cakes with cold eggs and they come out OK. It does make a difference when you're making a cake that's heavily dependent on egg whites ... like angel food cakes," he says. (According to The Science of Good Cooking, that's because cold eggs don't whip as well as room-temperature eggs, and when Kimball and crew tested them, those "finicky" cakes didn't rise right and became too dense.)

But Montagne is skeptical about whether Kimball has fully embraced this idea.

"Your recipe [for fluffy yellow layer cake] includes, I quote, 'bring all the ingredients to room temperature before beginning this recipe,'" she says.

"There's an old expression, do as I say and not as I do," Kimball says, laughing. "I am mature enough to recognize that we've held onto these myths in the kitchen.... We can grow. We can learn, too," he says.

"A little bit of science goes a long way in the kitchen, and it can make a big difference."

For more science tips and tricks from Chris Kimball, listen to the entire Morning Edition interview.

MONTAGNE: He and his crew of test cooks break it down in the new cookbook "The Science of Good Cooking." And Chris Kimball is here to share what he's calling kitchen myth busters. Hi, Chris.

CHRIS KIMBALL: Well, it's better than "Ghostbusters." We're not that creative in the kitchen.

(LAUGHTER)

MONTAGNE: All right, then. Let's start with one of the myths that I just mentioned: Marinating tenderizes meat. I just must say, I wouldn't have known until this moment that was a myth.

KIMBALL: Well, this is your awakening. You go online, there's thousands of recipes for Italian bottled salad dressing. You put it on chicken for an hour, then you grill it. The problem is marinades contain acids, usually vinegar, and those break down meat, but only to about a quarter of an inch of thickness. And when they break it down, they turn it to mush. They don't really tenderize it.

What does work is salting. Salt gets in, it allows the protein molecules to absorb water, it loosens up the protein fibers so it retains that water and it's easier to chew. So brining - really, that is marinades with salt in it - will help produce juicier, more tender meat.

MONTAGNE: And by way of example, you have brought us grilled chicken breast.

KIMBALL: Yeah. We have two samples in front of you. One of them was marinated without any salt in the marinade, and one was marinated with salt in the marinade. And hopefully - this is the part of science that's always nerve-wracking - you will discover the one that is salted. It'll have more flavor, of course, but it'll also be a little juicier.

MONTAGNE: I'm sitting here and there's the marinade, or the marinade, as I would call it. I'm tasting the one on my right. Tastes pretty good, Chris.

KIMBALL: That's good.

(LAUGHTER)

MONTAGNE: It's hard for you to make a bad piece of food. Here goes the one on my left. I do notice a difference. So the with salt is better.

KIMBALL: With salt...

MONTAGNE: More juicy. Let's move from meat to salad - or actually, salad dressing: the myth that oil and water don't mix. Now, this cannot be a complete myth, because this is my own experience, most people's experience. Bottled salad dressings, they break up. It doesn't seem as if you could shake it enough to get it to pour in a nice blend. So where's the myth there, Chris?

KIMBALL: Well, you're right. Unless you add something else to that mixture, oil and water won't mix or hold together very long.

MONTAGNE: So they do mix; they just won't hold together.

KIMBALL: Just. So what you want to do is look to emulsifiers. OK? Egg yolks have a terrific emulsifier in it called lecithin. One end of the lecithin molecule attaches to water and the other end attaches to oil and this creates a more stable emulsion.

So we did a test. We used nothing. We add a little mustard to it. We add a little mayonnaise, and then we used egg yolk. And we went from 15 minutes with nothing to, with mustard, 30 minutes. Mayonnaise got us up to an hour and a half. And a little egg yolk got us to three hours. So oil and water will mix for a while as long as you use an emulsion.

MONTAGNE: Does the mayonnaise or the egg yolk change it enough that you don't feel like you're having vinaigrette? I mean, does it turn it into a different kind of dressing?

KIMBALL: Yes. Certainly a mustard is going to change it a little bit. A classic French vinaigrette uses mustard. They almost all do. Mayonnaise, yeah, it'll look a little bit different, but it won't taste significantly different with mayonniase.

MONTAGNE: Chris Kimball of "America's Test Kitchen" is here talking with us about science and cooking, using science to dispel some kitchen myths. So what is another myth you want to clear up?

KIMBALL: Well, this has been a huge argument in the food world for as long as I've been in this world, about 30 years: Plastic cutting boards versus wood cutting boards. And everyone says, you know, wood boards are better than plastic or plastic's better than wood. We actually tested it.

We got salmonella bacteria in a laboratory, infected both boards with them, and then we tried a variety of things. What worked really well - roll the drums - killed over 99 percent of the bacteria, was hot, soapy water.

MONTAGNE: Hmm.

KIMBALL: So.

MONTAGNE: For both boards?

KIMBALL: For both boards.

MONTAGNE: Didn't matter.

KIMBALL: It didn't matter. It doesn't make any difference. So this is - finally we can put this one to bed.

INSKEEP: OK. I'm looking at another dish or, in this case, or actually, a soup. And it's gazpacho and I'm seeing a couple of examples. And what's the difference between the two?

KIMBALL: Well, the myth is you should always seed tomatoes. Turns out, that the seed and jelly, you know, it's the stuff you get rid of when you seed a tomato, has three times more flavor compounds, called glutamates, than the flesh. So when you seed the tomato you're actually throwing out most of the flavor. So we've made two Andalusian gazpatchos. One of them was made with seeded tomatoes, one made with unseeded tomatoes.

MONTAGNE: OK. Let me try. Pretty nice. Well, I have to say this one's better. I would have said - if I didn't know better, I would just say it's a better recipe or it's a better tomato.

KIMBALL: Well, it is a better recipe. It said don't seed the tomatoes.

MONTAGNE: Well, this is good because I never seeded tomatoes.

KIMBALL: Well, the only time I'd seed tomatoes, if you're making a little tomato dice, you know, as part of a salad or something. But if you're cooking in a soup or stew leave the seeds in.

MONTAGNE: Well, let's move on to another myth: never bake with cold eggs. Of all of these that we've talked about, that is the one that one always would think has the most science behind it.

KIMBALL: And it's the one nobody follows. It's like we're making cheesecake, everyone starts with cold cream cheese because we weren't smart enough to remember to take it out two hours before.

(LAUGHTER)

KIMBALL: You know, I'm like...

MONTAGNE: You mean people cheat.

KIMBALL: Right. For years I've made cakes, as you have, everybody has, with cold eggs and they come out OK. The truth is, that with a yellow cake using a whole egg it really doesn't make any difference. It does make a difference - there's a caveat here - when you're doing a cake that's heavily dependent on egg whites, not the whole eggs, for lift. That is like an angel food cake, for example, or a white cake.

Then the room temperature egg whites are important because they'll hold more air and you will get more lift.

MONTAGNE: I'm looking at the recipe for fluffy yellow layer cake. And your recipe includes, I quote, "Bring all the ingredients to room temperature before beginning this recipe."

KIMBALL: There's an old expression, do as I say and not as I do. Do you remember that?

(LAUGHTER)

MONTAGNE: Yeah.

KIMBALL: So, look, I am mature enough to recognize that we've held onto these myths over time in the kitchen. So, you know, we can grow. We can learn, too.

MONTAGNE: Very glad to be sharing that growth with you. Thank you very much.

KIMBALL: A pleasure. Well, you know, a little bit of science goes a long way in the kitchen, and actually can make a big difference.